C/2022 U2 (ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	14 Jan 2023	12.1	1.331 AU	0.619 AU	01h34m	+75°38'	110.3°	43.9°	83°
Nearest approach	28 Jan 2023	12.0	1.348 AU	0.566 AU	04h18m	+57°40'	118.2°	40.1°	101°
Today	18 Mar 2026	27.4	10.812 AU	10.531 AU	15h11m	-66°55'	103.8°	5.1°	308°

The interactive orbit chart above shows the comet's path through the solar system and its position at the given date. Green and blue lines are shown perpendicular to the ecliptic plane: Green if the path is above the ecliptic plane, blue if it is below. (Left-click and drag to rotate the view; Right-click and drag to move the view; Use scroll wheel to zoom in our out.)

Light curve

The light curve chart below shows the estimated development of the comet's magnitude. Blue and black dots are visual and photometric CCD observations from COBS. This lightcurve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 11.9 + 5 log[∆] + 10.0 log[r]). An additional green curve is displayed when an increase in apparent brightness is expected due to forward scattering of sunlight, which occurs when a dust-rich comet is located between the Earth and the Sun. (See Marcus 2007)

Charts

The all-sky chart below shows the path of the comet over the same period as the light curve. The comet's current position is marked yellow.

The following chart shows the short-term path of the comet in a field of view that is optimized for (~10x50) binoculars and finderscopes.

Orbital elements

The orbital elements of C/2022 U2 (ATLAS) are:

    e (Eccentricity)                : 0.9865700
    q (Perihelion distance)         : 1.3314910
    i (Inclination)                 : 48.25460
    Ω (Longitude of ascending node) : 304.38120
    ω (Argument of perihelion)      : 148.06480
    L (Longitude of perihelion)     : 281.84249
    B (Latitude of perihelion)      : 23.24494
    T (Time of perihelion passage)  : 2459958.73880
    P (Orbital period in years)     : 987.17

    Epoch                           : 2026 Mar 16
    Reference                       : MPEC 2026-E44

    Classification(s):              : Nearly isotropic; Returning (a < 10000 AU); External (P > 200 years)

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-03-17 00:00 UT   15 12 28.4   -66 50 46    10.539   10.800  102.6    5.2   306   27.4 
2026-03-18 00:00 UT   15 12 03.5   -66 53 33    10.534   10.807  103.3    5.1   307   27.4 
2026-03-18 18:57 UT   15 11 43.2   -66 55 42    10.531   10.812  103.8    5.1   308   27.4 
2026-03-19 00:00 UT   15 11 37.8   -66 56 16    10.530   10.813  103.9    5.1   308   27.4 
2026-03-20 00:00 UT   15 11 11.1   -66 58 55    10.526   10.820  104.6    5.1   309   27.4 
2026-03-21 00:00 UT   15 10 43.6   -67 01 31    10.522   10.827  105.2    5.1   310   27.4 
2026-03-22 00:00 UT   15 10 15.2   -67 04 03    10.518   10.834  105.9    5.1   311   27.4 
2026-03-23 00:00 UT   15 09 46.0   -67 06 31    10.514   10.840  106.6    5.1   312   27.4 
2026-03-24 00:00 UT   15 09 15.9   -67 08 54    10.510   10.847  107.2    5.0   313   27.4 
2026-03-25 00:00 UT   15 08 45.0   -67 11 14    10.506   10.854  107.8    5.0   314   27.4 
2026-03-26 00:00 UT   15 08 13.3   -67 13 30    10.502   10.860  108.5    5.0   315   27.4 
2026-03-27 00:00 UT   15 07 40.8   -67 15 41    10.499   10.867  109.1    5.0   316   27.4 
2026-03-28 00:00 UT   15 07 07.5   -67 17 48    10.495   10.874  109.8    5.0   317   27.4 

    Terminology:
            
    delta:  distance between comet and earth in AU
    radius: distance between comet and sun in AU
    magn:   magnitude (brightness) estimate    
    ra:     right ascension in hours (24h = 360deg)
    dec:    declination in degrees
    elong:  elongation in degrees (angle sun-earth-comet)    
    phase:  phase angle in degrees (angle sun-comet-earth)        
    AU:     Astronomical Unit (mean distance between earth and sun: 149597870.7 km      
    

Orbital elements usually provided by the MPC (Minor Planet Center).
Observations contributed by observers worldwide, via COBS (Comet Observation Database) or the MPC (Minor Planet Center)
Calculations by a modified version of AAPlus, a C# implementation of the AA+ project by PJ Naughter from the algorithms presented in the book "Astronomical Algorithms" by Jean Meeus.
NGC2000 dso catalog and star labels from VizieR as provided by the Strasbourg astronomical Data Center.
Tycho2 catalog from the ESO archive.